U.S. patent number 6,186,409 [Application Number 09/457,316] was granted by the patent office on 2001-02-13 for nozzles with integrated or built-in filters and method.
This patent grant is currently assigned to Bowles Fluidics Corporation. Invention is credited to Eric Koehler, Dharapuram N. Srinath.
United States Patent |
6,186,409 |
Srinath , et al. |
February 13, 2001 |
Nozzles with integrated or built-in filters and method
Abstract
A molded fluidic device having a power nozzle with a width W and
a coupling passage coupling a source of fluid to said power nozzle.
The coupling passage has a planar enlargement and a plurality of
posts spaced across the enlargement, the spacing S between each
post being less than the width of the power nozzle with the sum of
spacing S being greater than the width W.
Inventors: |
Srinath; Dharapuram N.
(Ellicott City, MD), Koehler; Eric (Woodstock, MD) |
Assignee: |
Bowles Fluidics Corporation
(Columbia, MD)
|
Family
ID: |
26809186 |
Appl.
No.: |
09/457,316 |
Filed: |
December 9, 1999 |
Current U.S.
Class: |
239/1; 137/833;
239/DIG.3; 239/600; 239/590; 239/589.1; 239/553; 239/462;
239/284.1; 239/101; 137/835; 264/DIG.76; 264/263; 264/250 |
Current CPC
Class: |
B05B
1/08 (20130101); B05B 15/40 (20180201); Y10S
264/76 (20130101); Y10T 137/2234 (20150401); Y10T
29/4998 (20150115); Y10S 239/03 (20130101); Y10T
137/2224 (20150401) |
Current International
Class: |
B05B
1/02 (20060101); B05B 1/08 (20060101); B05B
15/00 (20060101); B05B 001/08 () |
Field of
Search: |
;239/101,102.1,1,11,462,553,553.5,575,284.1,589.1,590,590.5,600,DIG.3
;137/826,833,835 ;264/250,263,DIG.76 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kashnikow; Andres
Assistant Examiner: Ganey; Steven J.
Attorney, Agent or Firm: Zegeer; Jim
Parent Case Text
REFERENCE TO RELATED APPLICATION
This application is the subject of provisional application Ser. No.
60/111,745 filed Dec. 10, 1998 and entitled FLUIDIC NOZZLES WITH
INTEGRATED OR BUILT-IN FILTERS.
Claims
What is claimed is:
1. In a molded fluidic spray device having a power nozzle with a
width W and a coupling passage coupling a source of liquid under
pressure to said power nozzle, the improvement wherein said fluidic
device includes a molded fluidic circuit and a housing having a
cavity into which said molded fluidic circuit is forcibly inserted
and wherein said coupling passage has an enlargement and a
plurality of posts spaced across said enlargement, the spacing S
between each post being less than the width of said power nozzle
with the sum of spacing S being substantially greater than said
width W and wherein said enlargement is planar and the dimensions
of said coupling passage, said planar enlargement and said spacing
S are such that the fluid flow rate from said source to said power
nozzle is substantially unaffected when one or more foreign
particles block any one or more of said spaces between said
posts.
2. The molded fluid device defined in claim 1 wherein said spacing
S between posts is substantially uniform.
3. In a molded fluidic spray device having a power nozzle with a
width W and a coupling passage coupling a source of liquid under
pressure to said power nozzle, the improvement wherein said
coupling passage has a planar enlargement and a plurality of posts
spaced across said planar enlargement, the space S between each
post being less than the width of said power nozzle with the sum of
spacing S being substantially greater than said width W and wherein
said device includes a planar fluidic oscillator and wherein said
enlargement is coplanar with said planar fluidic oscillator and the
dimensions of said coupling passage, said planar enlargement and
all said spacings S are such that the fluidic flow rate from said
source to said power nozzle is substantially unaffected when one or
more foreign particles obstructs any one of or more of said
spaces.
4. In a molded fluidic spray device having a power nozzle with a
width W and a coupling passage coupling a source of liquid under
pressure to said power nozzle, the improvement wherein said
coupling passage has an enlargement and a plurality of posts spaced
across said enlargement, the space S between each post being less
than the width of said power nozzle with the sum of spacing S being
substantially greater than said width W, wherein said device
includes a planar fluidic oscillator, wherein said fluid is a
liquid and said fluidic oscillator issues a fan spray of said
liquid droplets to ambient and wherein the dimensions of said
planar enlargement and said spaces S are such that said fan spray
is substantially unaffected when one or more foreign particles is
trapped in any one or more of said spaces.
5. The molded fluidic device defined in claim 4 wherein said
fluidic oscillator, said coupling passage and said posts are
injection-molded as an integral molding, and a housing member into
which said integral molding is inserted.
6. In a liquid dispensing fluidic nozzle having a molded housing
and an injection-molded fluidic circuit insert adapted to be forced
into said housing, said fluidic circuit insert having a liquid
dispensing outlet at a downstream end thereof, one or more power
nozzles at an upstream end thereof and a liquid flow passage formed
in a surface of said insert and adapted to be coupled to said one
or more power nozzles coupled to a source of liquid under pressure,
the improvement comprising:
an enlargement in said liquid flow passage and a plurality of
spaced posts dividing said enlargement in said liquid flow passage
into a plurality N of smaller flow spaces with the size of said
enlargement and the size of spacing between said posts being such
as to trap loose particles carried in liquid flowing through said
liquid flow passage without affecting the flow rate to said power
nozzles.
7. The method of providing a filter in an injection-molded fluidic
circuit having at least one power nozzle having a width W and a
coupling passage adapted to connect at least one power nozzle in
said fluidic circuit to a source of liquid under pressure
comprising injection-molding an enlargement in said coupling
passage with a plurality of spaced posts in said enlargement with
the spacing S between the posts being less than the width W of said
power nozzle and the sum of all said spacings S being significantly
greater than W so as to trap loose particles without affecting the
flow rate between said at least one power nozzle and said source of
liquid under pressure, inserting said fluidic circuit in a cavity
in a molded housing having one wall of said coupling passage
thereby completing said filter.
Description
BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION
Fluidic oscillators as shown in FIG. 1 are well known and
particularly useful in liquid spray applications such as washer
nozzles. Such fluidic oscillators are typically manufactured of
molded plastic and comprise a fluidic oscillator circuit OC or
silhouette molded in a chip or insert 13 and a housing 10 having a
cavity 11 into which the chip or insert 13 is forcibly inserted. A
source of fluid under pressure is supplied to the power nozzle PN
in the fluidic oscillator circuit OC by way of an inlet pipe or
barb 12. Care is taken in the design to assure a seal between the
housing internal surfaces and the mating surfaces of the chip or
insert. In mass manufacturing of such chips and housing, small
loose plastic particles can be carried by liquid flow and can clog
portions of the fluidic circuit or outlet thereby blocking the flow
of liquid (washer liquid in the case of a washer nozzle). In the
case of fluidic oscillators, this interrupts the oscillation
function.
There have been efforts to place screens or discrete filter screens
upstream of the fluidic circuit, but these expedients add cost and
complexity to the device. Thus, the problem solved and addressed by
the present invention is potential clogging of liquid flow devices.
The invention solves this problem by integrally providing extra
places or enlargements and spaced posts for contaminants or loose
particles to lodge or become trapped in areas other than main flow
areas so that there are additional flow passages or ways for liquid
to flow if a contaminant or particle blocks one or more passages or
spaces between posts.
The invention provides for low profiles in areas specifically
designed to encourage contaminants to flow into and stop in areas
other than the power nozzle or the main jet flow area. By providing
integral molded enlargements with spaced posts in areas as
described above, the fluidic nozzle can continue to function in
spite of partial upstream blockage in the enlargement area because
a power jet channel is still completely open. In the absence of the
present invention, contaminants usually flow directly into the
power nozzle or the main jet area, thereby making the system
nonfunctional.
The invention features a molded fluidic device having a power
nozzle with a width W and a coupling passage coupling a source of
fluid to said power nozzle. The coupling passage has an enlargement
and a plurality of posts spaced across the enlargement, the spacing
S between each post being less than the width of the power nozzle
with the sum of spacings S being greater than the width W and the
coupling passage and posts being integrally molded with the fluidic
device. The dimensions of the coupling passage, the planar
enlargement and the spacing S are such that the fluidic flow rate
from the source to the power nozzle is substantially unaffected
when a foreign particle blocks any one of the spaces between the
posts. In a preferred embodiment, fluidic is a liquid oscillator
which issues a fan spray of liquid droplets to ambient and wherein
the dimensions of the planar enlargement and the spaces S are such
that the fan spray is substantially unaffected when one or more
foreign particles is trapped in any one or more of the spaces. The
coupling passage and the posts are molded as an integral molding
with the fluid device. A housing member into which the integral
molding is inserted has a coupling to a source of liquid under
pressure.
The invention has advantageous usage in molded liquid-spray
nozzles, particularly when the liquid is sprayed to ambient; and
still more particularly when the liquid is a wash liquid to be
sprayed on a surface to be washed, such as vehicle glass.
Benefits of the present invention include the following:
1. Provides for prolonged life for the system in which the nozzle
is used.
2. Provides a filter mechanism free of cost compared to in-line
filters which require a separate component and some of which
require a hose to be cut to include the filter, install the filter,
etc.
DESCRIPTION OF THE DRAWINGS
The above and other objects, advantages and features of the
invention will become more apparent when considered with the
following specification and accompanying drawings, wherein:
FIG. 1 is a diagrammatic exploded illustration of a prior art
fluidic oscillator chip or insert and housing,
FIG. 2A is an illustration of a preferred embodiment of a fluidic
oscillator incorporating the invention, and FIG. 2B is a section
taken on lines 2--2 thereof,
FIG. 3A is an illustration of a further embodiment of the
invention, and FIG. 3B is a sectional view taken on lines 3--3
thereof,
FIG. 4 is a drawing illustrating a built-in filter concept of the
present invention as applied to a further type of fluidic
oscillator,
FIG. 5 is a further fluidic oscillator having a power nozzle
incorporating the present invention,
FIGS. 6A and 6B disclosure a circuit diagram of a further fluidic
oscillator incorporating the invention; in this case, the two
levels, FIG. 6B illustrating the flow to the power nozzle and FIG.
6A illustrating the fluidic oscillator itself with the input power
nozzle flow and built-in filter illustrated in dotted lines in
Figure B, and
FIG. 7 is an illustration of a built-in filter according to the
present invention in which the filter could be used in typical
nonfluidic dual-jet-type windshield washer nozzle; the same use can
be made for single and triple port nozzles of the same variety.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 2A and 2B, the fluidic circuit is of a
multiple power nozzle type oscillator 20 in which a pair of power
nozzles PN1 and PN2 issue jets of fluid (preferably liquid) into an
oscillation chamber OC in which a system of oscillating vortices is
set up which issues a sweeping jet through an outlet aperture OA to
ambient where the liquid jet breaks up into droplets. The fluid
feed for the power nozzles PN1, PN2 is constituted by a planar
passage 21 from a source of fluid 22. It will be noted that the
passage 21 is a planar enlargement in the flow of fluid to the
power nozzles PN1 and PN2. A portion of housing 10' is illustrated.
(Various other embodiments of the fluidic oscillator element is
disclosed in copending application Ser. No. 09/417,899 filed Oct.
14, 1999 and entitled FEEDBACK-FREE FLUIDIC OSCILLATOR AND
METHOD.
Integrally molded with the body of the circuit elements are a
plurality of posts or pillars 24-1, 24-2 . . . 24-N. The power
nozzles PN1, PN2 each have a width W and the spacing S between the
pillars or posts 24-1, 24-2 . . . 24-N need not be equal but
preferably are equal and the spacing S between each post 24 is less
than the width W of the power nozzle with the sum of the spacings S
being greater than the width of the power nozzle W. As noted above,
the enlargement is planar and essentially coplanar with the fluidic
circuit element 20.
The embodiment shown in FIGS. 3A and 3B is essentially the same as
the embodiment in FIG. 2 except that here the posts or pillars 24'
are in an arc. In this embodiment, the floor F of the fluidic
oscillator is flat up to the outlet OA' throat where there is a
downward taper as shown in the sectional view (FIG. 3B). In this
embodiment, the fluid flow is from the bottom of the element
through aperture 30 as indicated in FIG. 3B, but it could be from
the top. A portion of the housing is shown in FIG. 3B.
In the embodiment shown in FIG. 4, a different fluidic oscillator
FO is illustrated (this fluidic oscillator being of the type shown
in Bray U.S. Pat. No. 4,463,904 issued Aug. 7, 1984 and U.S. Pat.
No. 4,645,126 issued Feb. 24, 1987, incorporated by reference and
having the cold performance feature thereof). Note that in this
embodiment, the pillars or posts 24" are in a row, and the fluidic
feed FF is in advance of or upstream of that row of pillars or
posts 24".
In the embodiment shown in FIG. 5, the pillars 56-1, 56-2 . . .
56-N or posts need not be circular, round or square; they can be of
various shapes. In this embodiment, the fluidic oscillator FO' is
of the type disclosed in Stouffer U.S. Pat. No. 4,508,267 issued
Apr. 2, 1985, incorporated herein by reference. In each case, the
various multiple passages between power nozzle or input for feed
for liquid has a spacing S and the embodiment shown in FIG. 5, the
spacings can be varied. All of the spacings S between the posts are
less than the width W of the power nozzle with the sum of the
spacings being greater than W so that the fluidic flow from the
source to the power nozzle is substantially unaffected if a foreign
particle blocks any one or more of the spaces S between the
posts.
In the embodiment shown in FIGS. 6A and 6B, the fluidic oscillator
is of the reversing chamber type as disclosed in Raghu patent
application Ser. No. 09/427,985, filed Oct. 27, 1999 entitled
REVERSING CHAMBER OSCILLATOR. In this embodiment, the fluidic
insert 60 has two levels with the liquid or fluid coupling passage
61 and spaced posts 62 formed in the lower half shown in plan view
in FIG. 6B.
In the embodiment shown in FIG. 7, the integrated filter of this
invention is shown as used in a typical nonfluidic dual type
windshield washer nozzle. The same use can be made for a single and
triple port nozzles of the same variety. In this case, the posts or
pillars 70 in passage enlargement 71 are all in advance of the dual
spraying nozzles SN-1, SN-2.
While the invention has been described in relation to preferred
embodiments of the invention, it will be appreciated that other
embodiments, adaptations and modifications of the invention will be
apparent to those skilled in the art.
* * * * *